Change prepublishOnly to prepack

Author: wojtekmaj

package.json

@@ -13,7 +13,7 @@
     "clean": "rimraf dist",
     "jest": "jest",
     "lint": "eslint src/ --ext .jsx,.js",
-    "prepublishOnly": "yarn clean && yarn build",
+    "prepack": "yarn clean && yarn build",
     "test": "yarn lint && yarn jest"
   },
   "keywords": [